We’ve identified ten audio foibles that keep most video productions from sounding as good as they could.
Interesting, high-impact audio should be a goal of any creative videomaker, right up there with top-notch visuals. A good, clean, well-thought-out production deserves a good, clean audio track to support the video images. Oddly enough, the same mistakes keep popping up over and over to bring down the quality level of many videomaker’s efforts. To help make you aware of these recurring problems, here is a list of ten of
the most common audio production mistakes.
A good videomaker learns from his or her mistakes. This list of audio mistakes should allow you to quickly get a grasp on the most common audio problems and mistakes and help you to avoid them, hopefully before you make them. Experience is a great teacher, but the cost of experience is high.
Mistake #1: Thinking that making a video only involves images
Too much of the time, potentially good video productions are labeled “amateurish” due to the poor quality of the audio tracks. Thinking that a car can get you to your next destination without good fuel is similar to thinking you can make a good video without paying attention to the audio signal. The car might get you there, but will you be on time? Will you get there at all?
The time and effort you spend improving your audio will definitely pay off in the overall quality of your productions. The first step in doing better audio takes place in your head. You have to start thinking about the audio production process, and you have to believe that good audio makes a difference. It does!
Mistake #2: Too much distance
Trying to record a private conversation with the built-in microphone on your camcorder from across a
crowded hotel lobby would be an exercise in futility. Forget the fact that, with the proper lens, you’d have a fine video image of the persons conversing. You’re simply too far from your talent to pick up clean audio.
The best position for your camera is usually not the best position for your microphone. The best position for a microphone is usually on the subject, in the form of a lavalier mike. If you can’t plant a lav on your talent, get an external mike as close to your subject as possible.
The same problem is present in less severe situations as well. In fact, every time you use the built-in microphone on your camcorder, you will most likely experience this problem to some degree. If you must use your built-in microphone, get as close to the subject as possible and keep the microphone aimed at the subject, or source of the sound you intend to pick up, at all times. The audio quality improvement will be obvious.
Mistake #3: Shooting in an unnecessarily noisy environment
After spending hours putting together a video production, it is very disheartening to set down to edit tapes only to hear background noises that are so loud as to totally distract the listener. At this point, dubbing in new audio in a studio or re-shooting are your only solutions, and both processes are expensive and time consuming. Obviously, an ounce of prevention is worth a pound of cure in this case. Could a ten dollar microphone windscreen have saved you two hundred dollars in studio time or re-shooting expense?
Just paying a little bit of attention to the location and the actual sounds that are happening around you will allow you to be selective as to when you hit the record button and when you do not. Being attentive is not easy when an exciting visual is drawing your attention through the lens. However, this approach costs very little and has a big impact on the quality of your audio tracks.
Mistake #4: Not using headphones
If you consistently wear headphones to monitor the audio being recorded, environmental noises, as mentioned in mistake #3, will not be as much of a problem. The isolated audio signal being fed directly into your brain will allow you to be a much better judge of the quality of the audio signal. (This assumes, of course, that you are paying attention.) It also assumes that you have the proper attitude, as addressed in mistake #1, that a video production does not consist of video images alone.
If you wear a good set of sealed headphones, you save a lot of frustration and audio damage control when you edit. This leaves you with more time to be creative with the sound and images!
Mistake #5: Not understanding microphones
There is a mistaken idea in many minds that you can overcome the laws of physics by buying a special microphone. Instead, mikes depend on physical laws to operate, though “special” microphones can be used to improve your audio pickup under certain conditions.
To know that omnidirectional microphones pick up sound in all directions and that cardioid
microphones pick up sound better in the direction they are aimed will help you to select the appropriate microphone for the job at hand. Knowing that a wireless microphone system will free you from dragging around a cable and allow you to place the microphone element in a good location to pick up the audio signal is useful knowledge.
Try to learn all you can about microphone characteristics, but that knowledge alone will not be enough. Your best bet is to learn how to actually use your microphones.
Mistake #5: Not understanding microphone applications
The electromechanical transducer we call a microphone is your videotape’s link to the outside world of sound. Just as you use your eye and the video camera’s lens to capture appropriate images, you must also use your ears and a microphone to capture appropriate sounds to enhance the overall production. The way you use your microphones will determine, to a greater extent than the exact type or model of microphone, how well the audio signal is recorded and the quality of your finished audio product.
The most basic rule is to not use the microphone on the camcorder. No matter what
microphone you use off-camera, if you put it as close to the sound source as is possible you will usually have a better audio signal. If you can get the microphone close, you can better isolate the sounds you want to put on the tape from the sounds you do not want to put on the tape, such as noisy or distracting background sounds.
Mistake #6: Not matching signal levels
When you record many video segments and then editing them together to make one great video
production, there is a little audio problem that sometimes pops up. The audio on the individual segments,
which likely have been produced at various times and places, may not be recorded at the same audio signal
Keep a close eye on the audio level meter, if there is one. Simply paying attention to the audio
level in the headphones will make the job of editing much easier because the audio levels on the individual
segments will be closer. You can let AGC (auto gain control) do the work for you (and many consumer
camcorders offer only AGC), but sound quality may suffer. Which brings us to…
Mistake #7: Over-reliance on AGC
While the AGC circuit makes your audio levels consistent, it also makes the audio sound as if it’s
being “squashed.” The AGC circuit is very basic and does the job it is designed for very well–preventing
overload of the audio track on your videotape. However, it does not enhance audio quality. Pay attention to
the sound in the headphones. If you can defeat AGC on your camcorder, turn it off and set audio record
levels manually for each shot.
Mistake #8: Capturing unwanted hum
Hum is an annoying and unwanted addition to any audio signal. It’s sometimes generated by nearby
electrical devices or motors. At other times, it’s picked up by your audio cables or generated by a bad
ground on an electrical circuit.
Having good microphone cables and keeping all your electrical cables and cords in top condition
is the best way to eliminate hum from this source. Having your headphones on and being alert to hum in
the mix of background sounds is the best defense from picking up hum in the audible form. If some device
near your shooting location is creating hum, try to find a way to shut it off.
Mistake #9: Recording cable noise
Another very insidious culprit in the battle to eliminate audio noises is the mechanical noise created
by moving microphone cables. Cable noise can be very loud if your subject decides to handle, or “play,”
with the cable in order to release on-camera nervous energy.
To best eliminate this noise source, use high-quality handheld microphones. They have much
better internal shock isolation to reduce this problem. They also cost more, but are worth the higher cost.
With lavaliers, try to firmly attach the microphone element and cable to the subject’s clothing. If that is not
possible, a loop or loose knot in the cable will do wonders to keep the cable from rustling the microphone
element. Even a right-angle bend is effective because it interrupts the mechanical transmission of energy
from the cable to the microphone element.
You might also try to keep your subject calm and relaxed (good luck), and warn your subject
about touching the microphone cable. One final note–omnidirectional microphones are less sensitive to
picking up cable noise.
Mistake #10: Not being prepared
One mistake that we all make is going out into the world unprepared. This is the biggest time-wasting,
quality-reducing problem I know of. Running back to get something, or trying to find a cable in unfamiliar
surroundings is not just an inefficient use of time–it’s also extremely nerve-wracking.
Wireless microphones are wonderful and solve many of the audio problems associated with video
production. However, they sometimes don’t work due to other wireless devices interfering with them. Do
you always pack a wired microphone just in case? Wireless mikes also need a battery to operate. Do you
pack a spare?
Many television news crews pack a dependable omnidirectional microphone in their tool box for
situations when the wireless, or even the fancy wired microphone the talent likes, won’t do the job. They
know they can depend on that one mike to get the job done in the hot, the cold, the wet, the dry, the windy,
and the dangerous conditions they sometimes have to endure. They go out prepared for the worst.
Being prepared each time you leave to do a video shoot will save you a lot of frustration. It will
also allow you to better spend your time monitoring your audio signal in order to create a more
professional audio track to complement your images.
Audio has a big emotional impact on the viewer. In order to create the most emotional impact,
your audio must meet a high quality standard. This list of audio mistakes is designed to get you, the
videomaker, to pay more attention to your audio and to reach a new level of production quality by getting
control of your audio signals. A little knowledge, a little common sense and a little attention will go a long
way towards netting you better-sounding productions.